accessing file on second hard drives

I have just installed a new hard drive on my computer. I hooked up the old one hard drive a ADS USB addtional drive. I can now see all of my files but cannot access them. I receive an "access is denied" or "user does not have access privledges" message. How do I gain access to the files. I have tried changing the folder access and file sharing settings but I am still unable to access my old files. Does any one have a fix for this?